In 2005 the State of Kentucky, in partnership with the U.S. DOT, installed a system of technologies for the detection of high-risk heavy trucks at a weigh/inspection station on I-75 near London, Kentucky. The system, referred to as an Integrated Safety and Security Enforcement System (ISSES), was deployed to support Kentucky Vehicle Enforcement (KVE) by automatically accessing safety information from heavy trucks as they passed the scale house in the inspection station. The ISSES included a U.S. DOT number reader, an automated license plate recognition system (ALPR) and a laser-based system for classifying vehicles (e.g., based on the number of axles). The ISSES also had a detection system for bulk radiation and a thermal imaging inspection system to identify threats to homeland security.

Lesson Learned

An evaluation of the ISSES installed at the weigh/inspection station on I-75 near London, Kentucky found that the ISSES subsystems functioned according to performance specifications but the ISSES in general did not appear to have improved the efficiency of the inspection process. (Note: the scope of the evaluation did not include the homeland security functions of the ISSES.) The evaluation did however reveal several key lessons learned in terms of design and deployment that should be considered when planning for and installing an ISSES or similar inspection decision-aid system in the field, as follows:

Deploy an ISSES with a purpose and function that is in alignment with the state’s enforcement goals and inspection priorities. The Kentucky state inspection process emphasized the quantity of inspections completed, whereas the function of the ISSES was to increase the rate of Out of Service (OOS) orders issued. Each of these goals is valid but involves different procedures and priorities. Because the purpose of the ISSES was to help inspectors focus on the trucks with the worst safety records, it did not directly support the organizational goals of the inspectors and was not perceived in general by the inspectors as helping them achieve their goals in terms of quantity of inspection performed. The question of interdiction strategies for the location, although not a focus of the evaluation, is also relevant to the role of an ISSES in the broader organizational context.

Ensure that the weigh/inspection station has adequate staffing levels for inspectors to have the time and resources to use an ISSES. The staffing levels at the weigh/inspection station may have been a barrier to inspectors using the ISSES more in the day-to-day tasks. The inspectors in general did not attend to the information that was displayed on the ISSES display screens, but focused instead on the standard screening activities. Rather than using the ISSES, inspectors relied on their visual judgment and knowledge of the carriers to select trucks for inspection. Inspector feedback suggests that they considered watching the ISSES screen for information was not a productive use of time.

Provide adequate training on the ISSES so that the inspectors using it acquire the ability to read and interpret the ISSES displays. The evaluation revealed that most inspectors did not believe that they had received adequate training on the ISSES. Although training was provided upon the initial deployment in 2005 and periodically after, the general perception was that the inspectors did not consider their training to be adequate. Further, the level of on-site support for the ISSES appears to have been too low to have helped staff with questions and/or troubleshooting.

Include information on how the ISSES can augment the current inspection process in ISSES training. Current inspection selection is based primarily on visual observation, the weigh-in-motion (WIM) sensors and queries to safety data sources. Inspectors should be taught how to read the radiation monitor so that they can interpret the truck profile and understand the radiation dose rate values. Inspectors should be taught how to use the thermal imaging equipment so that they can recognize brake violations.

Periodically provide refresher training. Inspectors responding to user acceptance questions indicated that they were not familiar with the ISSES equipment. Conducting follow-up assessments on training effectiveness would help ensure that inspectors know how to use the ISSES. Providing ISSES user guides and contact information on-site is also valuable.

Upon deployment, integrate the ISSES with inspection, registration, licensing and safety databases so that it provides immediate value to the weigh/inspection station. At the Interstate 75 weigh/inspection station, the ISSES had not yet been integrated with state or federal safety information systems. As a result, information on the truck passing through ISSES equipment (e.g., the bulk radiation detection monitor, thermal imaging inspection system, vehicle classification system, U.S. DOT number reader, and license plate recognition system) was not integrated with Kentucky or federal safety data sources. Therefore, inspectors in general did not use ISSES information in their inspection selection decision.

Design and install the ISSES so that it performs as planned in the field. Physical constraints or realities in a weigh/station may affect the capabilities and performance of the ISSES. For example, trucks may drive through ISSES equipment at higher speeds than the posted speed limit (which is frequently 10 MPH on the ramp) or outside of the range of the equipment. The following examples highlight the need to check that the design parameters and the installation of the ISSES in the field will enable it to function as planned.

Build the Optical Character Recognition (OCR) system so that it will detect characters from trucks at speeds that they will be driving through the ISSES equipment. The evaluation team noted that the OCR system on the ISSES was designed for trucks traveling 15 MPH past the equipment. However, trucks routinely travel up to 20 or 30 MPH, which is over the speed limit. Similarly, the ability of the ISSES to identify trace radiation sources is weakened when vehicles travel faster than the design speed of 15 MPH. (There is a balancing act in terms of the optimum speed with which trucks should pass through a weigh/inspection station. Automated systems require a certain amount of time to capture data from moving trucks, but carriers are interested in moving trucks quickly through the station. Likewise, inspectors need sufficient time to make an inspection decision, but are also interested in preventing a backlog of trucks.

Position radiation monitors at a height that is high enough to capture the majority of a vehicle’s cargo area. The evaluation revealed that in weigh stations in Kenton and Simpson County, Kentucky, radiation detection panels were positioned so close to the ground that they missed the majority of a vehicle’s cargo area. The report noted that elevating the panels or adding additional panels is a significant cost. In addition, the evaluation found that the gamma alarm gave off frequent nuisance alarms because it became activated in the presence of naturally occurring but harmless material (e.g., bricks, porcelain, cat litter, ceramic tile) that emits gamma rays. The effect was that inspection staff tended to ignore the alarms.

Ask inspectors to provide input when selecting the location of the ISSES. The ISSES equipment may have been installed too close to the scale house to allow time for the inspectors to interpret information displayed on the ISSES display screen and decide whether to pull a truck over for inspection. The site should be further enough from the scale house to allow the time to process data and display information to the inspectors.

Consider carefully the advantages and potential costs of using off-the-shelf technology for an ISSES. Commercially available, off-the-shelf software may be initially less expensive than building custom software, but in the long run it can be costly due to the challenges of integrating different hardware and software systems. The evaluation found that there were operational problems that required re-designs.

The ISSES is designed to increase safety by identifying trucks that are likely to have Out of Service (OOS) violations. Identifying and inspecting high-risk trucks improves highway safety by reducing the probability of such trucks from being involved in a crash. The ISSES was designed to improve the efficiency of the inspection selection process by automatically detecting problems or potential problems on trucks driving through the weight/inspection station. However, the benefits of using an ISSES will not be realized unless the ISSES is technically integrated into information databases needed for inspection decisions and supports the priorities and procedures of the enforcement and inspection staff. Applying the lessons learned above to the design and deployment of ISSES will help realize its potential to improve safety.

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